Australian Datum Modernisation

Nothing on the surface of the Earth is fixed. The Earth's tectonic plates are constantly moving - in different directions and at different speeds. The Australian plate is moving in a north-easterly direction at a rate of about 7cm per year, or about 5mm per month.

This means the latitude and longitude of points in Australia are changing. Coordinates are calculated using a set of defined reference points called a geodetic datum. The current Australian datum, the Geocentric Datum of Australia 1994 (GDA94), is now over 20 years old.

We have moved approximately 1.6m since 1994, and Australia's coordinates are no longer accurate or in alignment with global navigation satellites systems (GNSS) such as GPS. This becomes highly significant when it comes to the use of applications that rely on accurate satellite positioning such as in-vehicle navigation; smartphones; automated mining operations; precision agriculture; and surveying where high absolute accuracies are required. To address this, Australia is implementing a new datum that will be known as the Geocentric Datum of Australia 2020 (GDA2020).

The Intergovernmental Committee on Surveying and Mapping (ICSM) is responsible for modernising Australia's Datum to ensure that all Australians can take advantage of the increased accuracy that current and future positioning and navigation technologies provide. The ICSM formed a dedicated working group, the GDA Modernisation Implementation Working Group, to oversee the implementation of the modernised datum across Australia's government, academic and industry sectors.

Geoscience Australia is the peak science agency responsible for technical development and maintenance of the national geodetic datum, and will update the coordinates of reference points that define Australia's new national datum, GDA2020. Geoscience Australia will also be assisting Australian Government agencies and Spatial Software providers to adopt the new datum.

Start Date 
Tuesday, 21 March, 2017 to Saturday, 21 March, 2020
Estimated completion date 
Saturday, 21 March, 2020
Percentage Complete 
Status Comment 
Australia's datum is being modernised in two stages. The first stage, the Geocentric Datum of Australia 2020 (GDA2020), will be released in 2017. Stage 2 will commence in January 2020, when users will be able to transition to a time dependant reference frame. This datum will be called the The Australian Terrestrial Reference Frame (ATRF) and will provide the Australian community with a sustainable, traceable, high-precision geodetic reference system capable of meeting the most demanding positioning requirements.
Program Activities 

Implement update programs

Start Timeframe 
2017 Q1
Delivery Timeframe 
The accuracy, currency and completeness of national foundation spatial dataset content meets the needs of stakeholders and emerging market trends.

Mar 16: Open GNAF and elevation datasets released. State borders and coastline updates continuing.


National Coordinates

Dataset Type 

The accurate position of highly stable reference stations across the nation is fundamental to all location-based technologies used in Australia. The resulting outputs of the National Positioning Infrastructure (NPI) Capability and national observations and measurements are the 3D (horizontal and vertical) coordinates of these reference stations maintained by the Commonwealth and States and Territories.

For further information, please refer to:

Main Funding Sources 
Point of Contact 
Mandate Comment 
As the Australian Government agency responsible for national positioning, Geoscience Australia facilitates technical and policy coordination on data and service standards, spectrum management, capability development, multilateral cooperation and legal traceability of position.
Input datasets 
ACT Survey Control Marks
National Geospatial Reference system
NT Coordinated Survey marks
Survey control register - Queensland series
SA Survey database
Survey Control Information Management System
LIST Survey Control
WA Geodetic Survey Marks (GESMAR)
VIC Survey Marks Enquiry Service SMES
Output datasets 
National Geospatial Reference system
Station Coordinates and Maps
Regulation 13 Certificates
Data and Site Logs
AUSPOS - Online GPS Processing Service
Australian Datum Modernisation
Agency/Working Group or Committee